I want to use two text from by the user in a Shiny apps, and pass that two text values to another function, I don't know what I'm missing because the code doesn't works and returns "input object not found"

I want to use that two inputs to make the contrasts in the makeContrasts() function. That function accept character vectors to make the contrasts

Sorry that I can't help.
I played with this setup briefly, but since your shiny-reprex leaves out makeContrasts and an example dataset, I have to work through a number of errors, making (probably bad) assumptions about what makeContrasts does and what a typical input file should look like.

I think you'll be more likely to find help here if you could supply makeContrasts and example data-file.

I think you'll be more likely to find help here if you could supply makeContrasts and example data-file.

Hello, sorry I add that info now, makeContrasts() builds a contrast matrix corresponding to specified contrast of a set of parameters as a numeric matrix, he takes 2 arguments , contrasts= a character vector specifying contrasts. and levels.

Thanks for the example input file, and letting us know that with that input file, we'd want to list "control" and "SIPGC" the Select Groups UI field. That was really helpful in getting this reproducible.